Explaining to Patients How Macronutrients Affect Obesity

During discussions with your patients about healthier eating, it can be helpful to explain how macronutrients can impact their weight loss goals. Patients can ultimately make better food choices and embrace a healthier mindset once they understand how macronutrients are important. Here’s how to get the conversation started. 

How to Explain Macronutrients?

Macronutrients are what we consume in the largest amounts and are essential for energy and bodily function. There are three types: carbohydrates, proteins, and fats. Lena Beal, MS, LD, CCTD, registered dietitian nutritionist and spokesperson for the Academy of Nutrition and Dietetics, explained how each plays a distinct role:

• Carbohydrates are the body’s preferred energy source, especially for the brain and muscles.
• Proteins are vital for repairing tissues, supporting immune function, and preserving lean muscle.
• Fats support hormone production and cell function and aid in the absorption of fat-soluble vitamins.

A practical explanation to offer patients might be: “Think of carbs as fuel, protein as building blocks, and fats as the support system — all are necessary, but in the right balance,” said Beal. 

How Obesity and Macronutrients Intersect

Your patients should understand how not all calories are created equal in how they affect hunger, metabolism, and fat storage.

“Explain to your patients how excess calorie intake — especially from highly processed carbohydrates and fats, without corresponding physical activity — leads to weight gain over time,” advised Beal.

In addition, have conversations about how refined carbs such as white bread and sugary snacks can spike blood sugar and insulin could lead to increased hunger and fat storage, how low protein intake can reduce satiety and lead to overeating, and how excess fats particularly from processed foods are calorie-dense and easy to overconsume, she said.

“Explaining to patients that weight gain is less about willpower and more about how the foods they choose influence their biology can reduce shame and increase motivation,” Beal said.

Doctors play a powerful role by not only offering medical advice but also helping patients connect the dots between food choices and metabolic health, Beal said.

“Small, consistent changes — rather than overhauls — make the difference. This underscores that long-term success isn’t about chasing a perfect diet but about creating a pattern that emphasizes nutrient-rich foods, mindful eating, and sustainable behaviors.”

The Calorie and Activity Connection

If you’re looking at weight management from a strictly diet and exercise view, it can be summarized as “calories in, calories out,” said Devon Wagner, MS, registered dietician at Ohio State Wexner Medical Center in Columbus, Ohio.

“Think of it as a balancing scale. Food intake, which is calories in, is on one side, while energy expenditure through movement and exercise, [which] is calories out, is on the other side,” she illustrated.

Wagner recommends telling your patients how when they’ve consumed more calories through their diet than what they are burning through exercise and activity, they gain weight. And explain the long-term consequences. “If this is done consistently for a long period of time, it will lead to obesity,” she said. 

Strategies Doctors May Suggest

As described, keep the focus on “calories out” than “calories in.” This can be done by increasing physical activity. “Even a simple goal to increase your steps per day can help,” said Wagner. The best course of action is to take fitness recommendations on a patient-by-patient basis. 

Next, help your patient focus on better diet choices by choosing foods that are less calorie-dense and more nutrient-dense. Examples of nutrient-dense foods are fruits, vegetables, whole grains, heart healthy fats, low-fat dairy, legumes, nuts and seeds, and lean protein. 

“All of these foods are packed full of nutrition and will keep you feeling satisfied longer than many ultraprocessed foods,” she said. 

Lastly, encourage more cooking at home. “What you cook at home will always be lower in calories, salt, and/or fat than at a restaurant,” said Wagner. “Aim to dine out two times per week or less.”

Considerations for Vegetarians or Vegans

While plant-based diets can be highly beneficial, they require attention to balanced macronutrient intake, said Beal. When consulting with patients who are vegan or vegetarians, it’s vital to ensure adequate protein through a variety of sources like legumes, soy, tofu, tempeh, seitan, nuts/seeds, and whole grains, she said.

In addition, primary care doctors should caution such patients to watch an over-reliance on refined carbs (eg, pasta, crackers, and vegan desserts), which can drive weight gain if not paired with enough fiber and protein. Another tip is to encourage healthy fats like avocado, olive oil, and flaxseed to keep the diet balanced.